The invention relates to a method of verifying a speaker from which a number of reference speech samples are obtained, a number of characteristics being derived in the same manner from each reference speech sample, the mean value being determined of the values of a characteristic of all reference speech samples, from the characteristic values of all reference speech samples there being determined a distance value, the characteristic mean values and the distance value being stored. From the speech sample to be verified there are derived characteristics in the same manner and the distance of this speech sample from the center point given by the characteristic mean values being formed from the sum of the squares of the differences between each characteristic value of the speech sample and the associated characteristic mean value, an O.K. signal being generated when the sum at the most equals the distance value.